ABSTRACT ? DEVELOPMENTAL CORE The overall goal of the Wadsworth Center?s Human Health Exposure Analysis Resource (WC-HHEAR) Developmental Core (Dev. Core) is to capitalize on the existing resources, expertise, and capacity at Wadsworth to develop and validate novel methods and analytical approaches for quantitative measurements of emerging chemicals in biospecimens, i.e., pushing the boundaries of human biomonitoring. Drs. Kannan and Parsons, the MPIs on this proposal, are leaders in their respective fields with more than 700 combined publications. They have spent the last two decades building the human biomonitoring program at Wadsworth ? in Dr. Parsons? Trace Elements Laboratory (TREL) and in Dr. Kannan?s Human Organics Biomonitoring Lab (HOBL). These efforts include assembling the current analytical capability; discovering emerging chemicals in human tissues and fluids; developing and validating new methods of analysis; and supporting the advancement of human health studies and the environment. Both HOBL and TREL have expansive lists of assays and capabilities that are part of the repertoire committed to support the WC-HHEAR targeted analysis resource (TAR). One of the Dev. Core?s functions will be to improve existing methods, requiring less sample volume for analysis, doing more with a limited amount of sample, improving detection limits, increasing sample throughput, reducing costs, and leveraging state-of-the-art technologies as they become available. For example, the proposed Dev. Core will investigate extractions that can be implemented for use on multiple classes of organic chemicals and improving detectability for trace elements using a new generation of technology based on inorganic tandem mass spectrometry. New capabilities will be developed in the Dev. Core and validated according to the international standards for single-laboratory method validation. The Dev. Core will build on its existing expertise with non-traditional matrices to offer more targets in more matrix types and will respond to HHEAR ? driven by either discoveries in the untargeted resource, increased demand from HHEAR clients, or suggestions from the HHEAR program office. The transfer of these improvements to current methods will be facilitated by the WC-HHEAR administrative core, where key staff are integrated into both the TAR and Dev. Core. It is only through the progress outlined above that high-quality, quantitative, exposome research can flourish.